If you can provide more information on which film you use, if you shot the film at the speed indicated on the box it came in, which chemistry you're using to develop your film, how it's diluted, and how you plan to agitate the film, it would help. If you don't know all of those, that's OK, you could get help with that here too.
30 minutes to wash film seems excessive. But you cannot over-wash film, so if you leave it in longer than you intended, there is no harm done.
For paper, you should always keep the print in the developer for the same amount of time. Then you adjust the 'density' in the print with exposure. Most chemistry says 2 or 3 minutes. I always develop my prints for 3 minutes, unless I use some type of special chemistry.
I hope that helps,
- Thomas